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1.
Environ Sci Technol ; 58(24): 10740-10751, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38771797

RESUMEN

The contamination status of novel organophosphate esters (NOPEs) and their precursors organophosphite antioxidants (OPAs) and hydroxylated/diester transformation products (OH-OPEs/di-OPEs) in soils across a large-scale area in China were investigated. The total concentrations of the three test NOPEs in soil were 82.4-716 ng g-1, which were considerably higher than those of traditional OPEs (4.50-430 ng g-1), OPAs (n.d.-30.8 ng g-1), OH-OPEs (n.d.-0.49 ng g-1), and di-OPEs (0.57-21.1 ng g-1). One NOPE compound, i.e., tris(2,4-di-tert-butylphenyl) phosphate (AO168 = O) contributed over 65% of the concentrations of the studied OPE-associated contaminants. A 30-day soil incubation experiment was performed to confirm the influence of AO168 = O on soil bacterial communities. Specific genera belonging to Proteobacteria, such as Lysobacter and Ensifer, were enriched in AO168 = O-contaminated soils. Moreover, the ecological function of methylotrophy was observed to be significantly enhanced (t-test, p < 0.01) in soil treated with AO168 = O, while nitrogen fixation was significantly inhibited (t-test, p < 0.01). These findings comprehensively revealed the contamination status of OPE-associated contaminants in the soil environment and provided the first evidence of the effects of NOPEs on soil microbial communities.


Asunto(s)
Antioxidantes , Ésteres , Organofosfatos , Microbiología del Suelo , Contaminantes del Suelo , Suelo , Suelo/química , Bacterias , China
2.
Ecotoxicol Environ Saf ; 252: 114577, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36709538

RESUMEN

Microplastics (MPs) are emerging contaminants in agricultural soil, whereas their effects on the rhizosphere microbial ecosystems and biogeochemical nitrogen cycles during plant growth remain unknown. Here, a 70-day greenhouse experiment was carried out with black and fluvo-aquic soil to evaluate the influence of polyamide (PA), polyethylene (PE), polyester (PES), and polyvinyl chloride (PVC) MPs on the bacterial communities and functions in the soybean rhizosphere. The PA treatment consistently affected the rhizobacterial alpha diversity in the fluvo-aquic soil at soybean vegetative and reproductive growth stages, whereas the PE, PES, and PVC treatments had a short-term effect on the bacterial alpha diversity. At two growth stages, 6 and 23 biomarkers were consistently abundant in the PA treatment in the black soil and fluvo-aquic soil, respectively, and order Rhizobiales was found to be a biomarker for PA MPs contamination in both soils. Additionally, PA treatment decreased bacterial network complexity and tightness, whereas the effects of the PE, PES, and PVC on bacterial co-occurrence patterns varied depending on the soil types. Furthermore, PES and PVC treatments inhibited ammonification processes in the soybean rhizosphere, and PE could temporarily inhibit ammonia oxidation and denitrification processes according to the variations of N-cycling gene abundances. These effects on soil N-cycling also varied with soil types and soybean growth stages. This study provides profound information for understanding of MPs residues on the assembly of the soybean rhizosphere communities and function during plant development.


Asunto(s)
Microbiota , Microplásticos , Plásticos , Glycine max , Rizosfera , Microbiología del Suelo , Bacterias/genética , Suelo/química , Nylons , Poliésteres , Polietileno
3.
Eur J Clin Pharmacol ; 77(12): 1853-1859, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34216249

RESUMEN

PURPOSE: The aim of this study was to investigate the expression levels of plasma miR-30a-5p, miR-101-3p, miR-140-3p and miR-141-3p and their relationship to dexmedetomidine efficacy and adverse effects in pediatric patients. METHODS: The expression levels of miR-30a-5p, miR-101-3p, miR-140-3p and miR-141-3p were measured by qRT-PCR in plasma of 133 pediatric patients receiving dexmedetomidine for preoperative sedation. We analyzed the relationship between miRNA abundance and dexmedetomidine response, including sedative effect and adverse effects, and assessed the predictive power of miRNAs for drug response. RESULTS: Among 133 pediatric patients, 111 patients were dexmedetomidine responders (UMSS ≥ 2) and 22 patients were non-responders (UMSS < 2). We observed higher expression levels of miR-101-3p and miR-140-3p in dexmedetomidine responders compared with non-responders (P < 0.05, P < 0.0001). In contrast, there was no significant difference in the expression levels of miR-30a-5p and miR-141-3p between responders and non-responders (P > 0.05). The plasma levels of miR-101-3p and miR-30a-5p were markedly downregulated in patients who experienced hypotension and bradycardia, respectively (P < 0.05). MiR-101-3p and miR-140-3p demonstrated a potential discriminatory ability between dexmedetomidine responders and non-responders, with AUC of 0.64 (P < 0.05) and 0.77 (P < 0.0001), respectively. The AUC of miR-101-3p in distinguishing patients without hypotension was 0.63 (P < 0.05). The AUC of miR-30a-5p in distinguishing patients without bradycardia was 0.74 (P < 0.05). CONCLUSION: Our study demonstrated that circulating miR-101-3p, miR-140-3p and miR-30a-5p might be used as a blood-based marker for dexmedetomidine efficacy and safety in pediatric patients.


Asunto(s)
Dexmedetomidina/uso terapéutico , Hipnóticos y Sedantes/uso terapéutico , MicroARNs/sangre , Biomarcadores , Preescolar , Dexmedetomidina/administración & dosificación , Dexmedetomidina/efectos adversos , Femenino , Humanos , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/efectos adversos , Lactante , Masculino
4.
Transp Policy (Oxf) ; 106: 226-238, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33867701

RESUMEN

This paper demonstrates that transportation networks may be used to assess and predict the regional risk of COVID-19 infection from the outbreak. We use China's high-speed rail (HSR) network at the scale of prefecture level to assess, based on a probabilistic risk model, the risk of COVID-19 infection from Wuhan to the country's 31 province-level regions at the early stage of domestic spread. We find that the high-risk regions are mainly distributed along the southern half of Beijing-Hong Kong HSR line, where a large number of infection cases have been confirmed at the early stage. Furthermore, the two components of the infection risk, namely, the probability (proxied by the region's correlation with Wuhan through HSR) and the impact (proxied by the region's population with mobility), can play different roles in the risk ranking for different regions. For public health administrators, these findings may be used for better decision making, including the preparation of emergency plans and supplies, and the allocation of limited resources, before the extensive spread of the epidemic. Moreover, the administrators should adopt different intervention measures for different regions, so as to better mitigate the epidemic spread according to their own risk scenarios with respect to the probability of occurring and, once occurred, the impact.

5.
Int J Inf Manage ; 46: 10-22, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32287831

RESUMEN

China is severely exposed to natural hazards. Currently, there are more than 5.5 million contingency plans for handling various incidents. Similar to those produced in other counties, the paper-based plans in China are limited in that emergency responders cannot easily extract helpful information for them. In this paper, a knowledge-based system will be proposed for providing different stakeholders with helpful information in the emergency response. The conceptual model is the core for the whole system, which can link plans in the physical world and the ontology in the cyber world.

6.
ScientificWorldJournal ; 2014: 545049, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25045737

RESUMEN

The intuitionistic linguistic variables are easier to describe the fuzzy information which widely exists in the real world, and Bonferroni mean can capture the interrelationship of the individual arguments. However, the traditional Bonferroni mean can only process the crisp number. In this paper, we will extend Bonferroni mean to the intuitionistic linguistic environment and propose a multiple attribute decision making method with intuitionistic linguistic information based on the extended Bonferroni mean which can consider the interrelationship of the attributes. Firstly, score function and accuracy function of intuitionistic linguistic numbers are introduced. Then, an intuitionistic linguistic Bonferroni mean (ILBM) operator and an intuitionistic linguistic weighted Bonferroni mean (ILWBM) operator are developed, and some desirable characteristics of them are studied. At the same time, some special cases with respect to the parameters p and q in Bonferroni are analyzed. Based on the ILWBM operator, the approach to multiple attribute decision making with intuitionistic linguistic information is proposed. Finally, an illustrative example is given to verify the developed approach and to demonstrate its effectiveness.


Asunto(s)
Toma de Decisiones , Lingüística , Algoritmos , Lógica Difusa , Humanos
7.
Sci Total Environ ; 773: 145640, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33582358

RESUMEN

Microplastics (MPs) are a contaminant of increasing concern in the environment. However, the impacts of MPs on soil ecosystems and biogeochemical processes like nitrogen cycle have not been well elucidated. In this study, we designed an indoor microcosm experiment to investigate the effects of exposure to low density polyethylene (LDPE) MPs on soil bacterial community and nitrogen cycling function over a 90-day incubation. Next-generation sequencing of the 16S rRNA genes revealed that both 2% and 7% LDPE MPs exposure slightly affected the soil bacterial diversity. Further analysis at the genus level showed differential tolerance to LDPE MPs, the genera Pedomicrobium, Steroidobacter, Pseudonocardia, Nitrospira and Turicibacter were enriched in the soil with 2% (w/w) LDPE MPs amendment, while the genera Pedomicrobium, Mycobacterium and Hyphomicrobium were significantly enriched in the soil with 7% (w/w) LDPE MPs amendment on days 15 and 30. Co-occurrence network analysis further suggested that LDPE MPs changed bacterial network complexity and modularity and Acidobacteria formed intimate associations with each other in responding to LDPE MPs exposure. Additionally, LDPE MPs in soil increased the abundance of nifH, AOBamoA and nirK genes involved in nitrogen cycling in different incubation phases compared to the control. The abundance of AOAamoA genes decreased on day 15 and then increased. Conversely, the abundance of nirS genes increased during the first 15 days and then decreased. These results suggested that both 2% and 7% LDPE MPs impact soil bacterial network structure and alters functional groups involved in soil nitrogen cycling processing.


Asunto(s)
Microbiota , Microplásticos , Nitrógeno , Ciclo del Nitrógeno , Plásticos , Polietileno , ARN Ribosómico 16S , Suelo , Microbiología del Suelo
8.
Sci Total Environ ; 770: 144730, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33736380

RESUMEN

Clomazone, a widely used herbicide, is mainly used in soybean fields. We previously found that clomazone alters Proteobacteria and Nitrospirae abundances and also alters urease activity, which result in changes in NH4+ and NO3- contents in soil nitrogen cycling. It remains unknown, however, how the co-occurrence patterns of species and functions of soil ecosystems change in response to clomazone applications in soil. We designed a 3-month greenhouse experiment to investigate soil microorganism dynamics in response to clomazone. Clomazone was applied at three doses (e.g., T1, T10, T100), which significantly increased bacterial abundance at days 15 and 60. Fungal abundance was stimulated at day 30 in T10-treated soils, whereas fungal abundances decreased in T100-treated soils at day 15. Clomazone altered bacterial and fungal community structures. Network analyses showed more complex and highly connected microbial communities in clomazone-treated soils. Moreover, an Acidobacteria-dominated cluster was identified within each network of clomazone-treated soils. Clomazone applied at the recommended rate decreased the functional groups that were associated with denitrification and hydrogen oxidation at days 15 and 60, and enhanced photoheterotrophy from days 30 to 60. High clomazone inputs increased trophic types (e.g., chemoheterotrophy, phototrophy, photoautotrophy and cyanobacteria) and C cycling functional groups (e.g., fermentation and cellulolysis). The half-life of clomazone ranged from 40.1 to 93.5 days in three cases. Our results provide important information for use of this herbicide.


Asunto(s)
Oxazolidinonas , Suelo , Isoxazoles , Microbiología del Suelo
9.
Chemosphere ; 257: 127206, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32502737

RESUMEN

Microplastics (MPs) could act as a vector for various kinds of pollutants due to their small size. Compared to nonpolar and nondegradabale MPs, the sorption of organic pollutants on polar and degradable MPs has been seldom studied. In this study, the sorption behavior of two nonpolar polycyclic aromatic hydrocarbons (PAHs, phenanthrene and pyrene), two polar derivates of PAHs (1-nitronapthalene and 1-napthylamine) and a heterocyclic chemical (atrazine) by three polar MPs including polybutylene succinate (PBS), polycaprolactone (PCL) and polyurethane (PU) and a typical nonpolar MP, polystyrene (PS) were investigated. The sorption followed the pseudo-second-order kinetics and sorption equilibrium was achieved within 5 days. Sorption isotherms could be well fitted by both Linear (R2>0.946) and Freundich models (R2>0.945) and the values of nonlinear index (n) from Freundlich model in most cases were close to 1, suggesting that hydrophobic partition was a primary process controlling the sorption. The sorption coefficients (Kd) of the five organic compounds ranged from 29. 6 to 1.42 × 105 (L/kg). The log KOC/log KOW of PAHs and derivates of PAHs on polar MPs were greater than 1, especially for 1-naphthylamine (1.30-1.40), confirming the great contribution of hydrogen bonding. PU contains a benzene ring and showed greater sorption compared the other two polar MPs, indicating the existence of π (n) -π electron donor-acceptor interactions. Morevoer, the sorption of phenanthrene and pyrene on PU were better fitted by Langmuir model and the maximum adsorption capacities were 1.06 × 104 and 5.87 × 103 mg/kg, respectively.


Asunto(s)
Contaminantes Ambientales/química , Microplásticos/química , Adsorción , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Compuestos Orgánicos , Fenantrenos , Plásticos/química , Hidrocarburos Policíclicos Aromáticos/análisis , Poliestirenos , Poliuretanos , Pirenos
10.
Artículo en Inglés | MEDLINE | ID: mdl-29090615

RESUMEN

We have developed a rapid, multi-compound analytical method for measuring residues of the pesticides thiamethoxam and its metabolite, clothianidin; fipronil and its three metabolites, fipronil sulfone, fipronil sulfide, and fipronil desulfinyl; and pyraclostrobin in unprocessed foods (rice, corn, cucumbers, tomatoes, apples, and bananas) by ultra-performance liquid chromatography coupled to tandem mass spectrometry. Acetonitrile was used as the extraction solvent, and an octadecylsilane-dispersive SPE was used to clean up the analytes, which were then separated through a UPLC HSS T3 column connected to a tandem mass spectrometer via an electrospray ionisation source. The linearity of this method for the target analytes was excellent (R2 ≥0.990) in the concentration range of 5-1000 µg kg-1. The average recoveries of the seven compounds at concentrations of 10, 100, and 1000 µg kg-1 from six spiked matrix samples ranged from 73.6 to 110.6%, all with RSD values of ≤19.7%. The limit of quantification was 10 µg kg-1. The method validated the effectiveness of the method for routine monitoring the residue of these pesticides and their metabolites in foods.


Asunto(s)
Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Plaguicidas/análisis , Plaguicidas/metabolismo , Cromatografía Líquida de Alta Presión , Cucumis sativus/química , Solanum lycopersicum/química , Malus/química , Musa/química , Neonicotinoides/análisis , Neonicotinoides/metabolismo , Nitrocompuestos/análisis , Nitrocompuestos/metabolismo , Oryza/química , Oxazinas/análisis , Oxazinas/metabolismo , Espectrometría de Masas en Tándem , Tiametoxam , Tiazoles/análisis , Tiazoles/metabolismo , Zea mays/química
11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(4 Pt 2): 046105, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17155131

RESUMEN

We propose two types of evolving networks: evolutionary Apollonian networks (EANs) and general deterministic Apollonian networks (GDANs), established by simple iteration algorithms. We investigate the two networks by both simulation and theoretical prediction. Analytical results show that both networks follow power-law degree distributions, with distribution exponents continuously tuned from 2 to 3. The accurate expression of clustering coefficient is also given for both networks. Moreover, the investigation of the average path length of EAN and the diameter of GDAN reveals that these two types of networks possess small-world feature. In addition, we study the collective synchronization behavior on some limitations of the EAN.

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